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Small dissymmetry, yet large effects on the transport propertiesof electrolytes based on imide salts: Consequences on performancein Li-ion batteries

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Journal of Energy Chemistry 2022年第2期31卷 352-366页

作者： Joseph Chidiac Laure Timperman mérièm Anouti Laboratoire PCm2E Universitéde ToursParc de Grandmont37200 ToursFrance

To gain better insight into the influence of the anion size and symmetry on the transport properties and thermal stability of an electrolyte based on lithium(fluorosulfonyl)(trifluoromethanesulfonyl)-imide(FTFSI)salt,we performed the physical and electrochemical characterization of an electrolyte based on FTFSI incorporated in standard binary(3 EC/7 EmC)and ternary(EC/PC/3 DmC)alkylcarbonate *** applying the Jones-Dole-Kaminsky(JDK),Eyring and Arrhenius empirical models to the electrolyte viscosity we show that the activation enthalpy and entropy energy barriers(ΔH≠,ΔS≠)for viscous flow are between 12 and 15 kJ·mol^(-1).They are strongly dependent on the solvent nature and are significantly lower than their symmetric anions LiFSI and LiTFSI(19-20 kJ·mol^(-1))in the binary ***,the hydrodynamic radius,rs,calculated by JDK,and the ionicity behavior illustrated by the Walden role,showed that the FTFSI anion is outside the solvation sphere(rs>0.6 nm)which is smaller in the case of an EC/EmC solvent *** the 3 EC/7 EmC solvent mixture,LiFTFSI is less conductive than in the ternary mixture i.e.,σ_(max)=8.9 mS cm^(-1) at C_(max)=1.1 mol L^(-1) for 3 EC/7 EmC and,σ_(max)=10.5 mS cm^(-1) at max=0.7 mol L^(-1) for EC/PC/3 DmC,due to a strong solvation and a greater association of FTFSI ions in the binary solvent *** thermal stability of FTFSI based electrolytes was determined by the shift of the evaporation temperature of the volatile solvents(DmC,EmC)in the presence of salt,towards the higher *** feature is visible on the thermograms obtained by DSC both with the liquid electrolyte and with charged LmO cathodes in presence of *** consequences of these properties on the electrochemical behavior of a graphite(Gr)half-cell,a lithium metal(Li)anode and a manganese lithium oxide(LmO)cathode demonstrated on the one hand the formation of a thick solid electrolyte interphase(SEI)on graphite that consumed a significant amou

关键词： LiFTFSI Electrolyte Viscosity Interface Li-ion battery

Structural,electrical and optical characterization of InGaN layers grown by mOVPE

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Chinese Physics B 2009年第9期18卷 4007-4012页

作者： Yildiz A ztürk m Kemal Bosi m zelik S Kasap m Physics Department University of Ahi EvranAsikpasa Kampusu mineral Analysis and Technology Department MTA ImEm-CNR Institute Area delle Scienze 37/AI-43010 FontaniniParmaItaly Physics Department University of Gazi

We present a study on n-type ternary InGaN layers grown by atmospheric pressure metalorganic vapour phase epitaxy （mOVPE） on GaN template/（0001） sapphire substrate. An investigation of the different growth conditions on n-type InxGa1-xN （x = 0.06 -- 0.135） alloys was done for a series of five samples. The structural, electrical and optical properties were characterized by high resolution x-ray diffraction （HRXRD）, Hall effect and photolumineseence （PL）. Experimental results showed that different growth conditions, namely substrate rotation （SR） and change of total H2 flow （THF）, strongly affect the properties of InGaN layers. This case can be clearly observed from the analytical results. When the SR speed decreased, the HRXRD scan peak of the samples shifted along a higher angle. Therefore, increasing the SR speed changed important structural properties of InGaN alloys such as peak broadening, values of strain, lattice parameters and defects including tilt, twist and dislocation density. From PL results it is observed that the growth conditions can be changed to control the emission wavelength and it is possible to shift the emission wavelength towards the green. Hall effect measurement has shown that the resistivity of the samples changes dramatically when THF changes.

关键词： InGaN mOVPE substrate rotation total H2 flow

Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVARI m.R.HOmAEINEZHAD Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(Amm)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(Amm) nonlinear motion analysis

A highly concentrated vanadium protic ionic liquid electrolyte for the vanadium redox flow battery

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Journal of Energy Chemistry 2021年第6期30卷 238-246,I0007页

作者： Georgios Nikiforidis Amal Belhcen mérièm Anouti Laboratoire PCm2E Universitéde ToursParc de Grandmont37200 ToursFrance LE STUDIUm Institute for Advanced Studies 45000 OrléansFrance

A protic ionic liquid is designed and implemented for the first time as a solvent for a high energy density vanadium redox flow *** being less conductive than standa rd aqueous electrolytes,it is thermally stable on a 100 ℃ temperature window,chemically stable for at least 60 days,equally viscous and dense with typical aqueous solvents and most importantly able to solubilize to 6 mol L^(-1) vanadium sulfate,thus increasing the VRFB energy density by a factor of *** measurements revealed quasi-reversible redox transitions for both catholyte and anolyte at 25 ℃ while a proof-of-concept redox flow cell with the proposed electrolyte was tested for a total of 150 cycles at 25 ℃,showing an open circuit potential of 1.39 V and energy and coulombic efficiencies of 65% and 93%,***’s more,the battery can be equally cycled at 45℃ showing good thermal *** study underlines a new route to improve the energy-to-volume ratio of energy storage system.

关键词： Protic ionic liquids Redox flow battery Electrolyte High energy density

Atom–field entanglement in the Jaynes Cummings model without rotating wave approximation

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Chinese Physics B 2015年第4期24卷 70-75页

作者： m.mirzaee m.Batavani Department of Physics Faculty of Science Arak University

In this paper, we present a structure for obtaining the exact eigenfunctions and eigenvalues of the Jaynes-Cummings model （JCm） without the rotating wave approximation （RWA）. We study the evolution of the system in the strong coupling region using the time evolution operator without RWA. The entanglement of the system without RWA is investigated using the Von Neumann entropy as an entanglement measure. It is interesting that in the weak coupling regime, the population of the atomic levels and Von Neumann entropy without RWA model shows a good agreement with the RWA whereas in strong coupling domain, the results of these two models are quite different.

关键词： atom-photon interaction Jaynes--Cummings model quantum entanglement

Adaptive Increasing-Order Synchronization and Anti-Synchronization of Chaotic Systems with Uncertain Parameters

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Chinese Physics Letters 2011年第11期28卷 49-51页

作者： m.mossa Al-sawalha m.S.m.Noorani Faculty of Science Mathematics DepartmentUniversity of HailKingdom of Saudi Arabia Center for modelling&Data Analysis School of Mathematical SciencesUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia

We elaborate the concept of increasing-order synchronization and anti-synchronization of chaotic systems via an adaptive control scheme and modulation *** is shown that the dynamical evolution of a third-order chaotic system can be synchronized and anti-synchronized with a fourth-order chaotic system even though their parameters are *** analysis and numerical simulations are carried out to verify the results.

关键词： parameters chaotic system

Ion acoustic shock and periodic waves through Burgers equation in weakly and highly relativistic plasmas with nonextensivity

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Plasma Science and Technology 2017年第1期19卷 7-19页

作者： m G HAFEZ N C ROY m R TALUKDER m HOSSAIN ALI Department of of Applied mathematics University of Rajshahi Rajshahi-6205 Bangladesh Department of mathematics Chittagong University of Engineering and Technology Chittagong-4349Bangladesh Plasma Science and Technology Lab Department of Applied Physics and Electronic EngineeringUniversity of Rajshahi Rajshahi-6205 Bangladesh

A comparative study is carried out for the nonlinear propagation of ion acoustic shock waves both for the weakly and highly relativistic plasmas consisting of relativistic ions and qdistributed electrons and *** Burgers equation is derived to reveal the physical phenomena using the well known reductive perturbation *** integration of the Burgers equation is performed by the（G￠/G）-expansion *** effects of positron concentration,ion–electron temperature ratio,electron–positron temperature ratio,ion viscosity coefficient,relativistic streaming factor and the strength of the electron and positron nonextensivity on the nonlinear propagation of ion acoustic shock and periodic waves are presented graphically and the relevant physical explanations are provided.

关键词： electron-positron-ion plasmas ion acoustic shock and periodic waves weakly and highly relativistic effects Burgers equation

Characterization of ion irradiated silicon surfaces ablated by laser-induced breakdown spectroscopy

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Chinese Physics B 2018年第8期27卷 505-510页

作者： T Iqbal m Abrar m B Tahir m Seemab A majid S Rafique Department of Physics Faculty of Sciences University of Gujrat Hafiz Hayat Campus Department of Physics Hazara University Mansehra Department of Physics University of Engineering and Technology (UET)Lahore Pakistan

Low energy metallic ions, generated by a Q-switched Nd：YAG laser （1064-nm wavelength, 10-mJ energy, 9-nm 12-ns-pulse width, 1011 W/cm2 intensity） irradiated on a silicon substrate to modify various properties, such as electrical, morphological, and structural modifications. Thomson parabola technique is used to calculate the energy of these metallic ions whereas the electrical conductivity is calculated with the help of Four-point probe. Interestingly circular tracks forming chain like damage trails are produced via these energetic ions which are carefully examined by optical microscopy. It is observed that excitation, ionization, and cascade collisions are responsible for surface modifications of irradiated samples. Four-point probe analysis revealed that the electrical conductivity of substrate has reduced with increasing trend of atomic number of irradiated metallic ions （A1, Ti, Cu, and Au）. The x-ray diffraction analysis elucidated the crystallographic changes leading to reduction of grain size of N-type silicon substrate, which is also associated with the metallic ions used. The decreasing trend of conductivity and grain size is due to thermal stresses, scattering effect, structural imperfections, and non-uniform conduction of energy absorbed by substrate atoms after the ion irradiation.

关键词： ablation Thomson parabola technique four-point probe

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIZABAD m.H.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** Hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)